Run an A/B test
Send two versions of one campaign, see which one performs better and use the winner in your next send.
An A/B test sends two versions of the same campaign. Half of your audience gets version A, the other half version B. The report then shows which one worked better.
Why it helps
- You learn what your audience responds to instead of guessing.
- Each test makes the next campaign stronger.
- The split is fair: every mailbox provider is divided evenly and both versions go out at the same time.
Choose what to test
You test one thing at a time.
- Subject line: two subject lines and preview texts, one design. MailGraf compares opens.
- Content: one subject line, two designs. MailGraf compares clicks.
Turn on the test
Open Campaign settings
In the campaign wizard, click Settings in the top bar.Turn on Run an A/B test
A/B tests are included in the Pro plan and above.Choose Subject line or Content
The campaign now carries an A/B TEST · SUBJECT or A/B TEST · CONTENT chip, so you always know what you are testing.
Set up a subject line test
Go to the Setup step
Enter the Subject and Preview text for version A as usual.Choose Version B
At the top of the Subject and preview text card, switch from Version A to Version B. Write a different subject line and preview text.Check the inbox preview
Gmail, Outlook and Apple Mail show the version you selected.
Set up a content test
Go to the Design step
Choose Version A above the design card and create your design.Choose Version B
Click Copy from A to start from the same design, or click Change template.Click Edit design
Change what you want to test, for example the headline or the button.Click Show comparison
You find it at the top of the design card. Both designs open side by side.
Change one thing
Change one element only. If the headline and the button both differ, you cannot tell which one made the difference.
Test and send
Check the Audience step
The A/B split card shows how many contacts get each version.Open the Review step
Both versions are listed. If version B is missing something, the Almost ready box tells you, for example Add a design for version B.Click Send a test
Under Send as, choose Version A, Version B or Both.Send the campaign
Every recipient gets one version only.
Read the result
Open the report
On the Campaigns page, click the name of the sent campaign.Open the A/B test tab
The card at the top shows which version is ahead and by how many points.Read the line under it
Enough data to trust this result. means you can rely on the winner. Otherwise treat the result as a hint.Compare the details
The table shows sent, opens, clicks, bounces, unsubscribes and complaints for each version. Version A and B over time shows how the two versions moved.
On the Click map, Technology and Locations tabs, use Version details to look at All, A or B. On a contact's profile, the campaign shows an A or B chip.
How much data is enough
MailGraf names a winner only when each version has reached at least 100 recipients and the difference is clear. Larger audiences give clearer results.
Frequently asked questions
Does MailGraf send the winner to everyone automatically?
No. Both versions go out together to their half of the audience. Use the result to shape your next campaign.
If I turn the test off, is version B deleted?
No. Version B is kept but not sent. Turn the test back on and it returns.
Can I use an A/B test in an automation?
No. A/B tests are available on campaigns only.
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